Digital indocyanine-green angiography in chorioretinal disorders

Clinical applications of aqueous angiography in glaucoma

Aqueous humor outflow (AHO) pathways are the main site of resistance causing elevated intraocular pressure in glaucoma, especially primary open-angle glaucoma patients. With the recently introduced technique of aqueous angiography (AA); functional, real time assessment of AHO from proximal (trabecuar meshwork) to distal pathways under physiological conditions has been made possible. AHO pathways are segmental, and AA can identify high-flow region (increased angiographic signals) and low flow region (decreased angiographic signals) in an individual. With the introduction of canal-based minimally invasive glaucoma surgeries (MIGS), the assessment of AHO can help guide the placement of stents/incisions during MIGS procedures. This can allow individualized and targeted MIGS procedures in glaucoma patients for better results. Based on the density of AHO pathways visualized on AA, surgeons can decide whether to perform MIGS or conventional glaucoma surgery for improved outcomes for the patient. Immediate intraoperative assessment for functionality of the MIGS procedure performed is possible with AA, allowing for surgical adjustments of MIGS procedure in the same sitting, if needed. This review provides a summary of the studies performed with AA to date, with a special focus on Indian patients. It covers the basics and clinical applications of AA for improving surgical outcomes in glaucoma patients.

Surgical margin status outcome of intraoperative indocyanine green fluorescence-guided laparoscopic hepatectomy in liver malignancy: a systematic review and meta-analysis

BACKGROUND

Hepatectomy stands as a curative management for liver cancer. The critical factor for minimizing recurrence rate and enhancing overall survival of liver malignancy is to attain a negative margin hepatic resection. Recently, Indocyanine green (ICG) fluorescence imaging has been proven implemental in aiding laparoscopic liver resection, enabling real-time tumor identification and precise liver segmentation. The purpose of this study is to conduct a systematic review and meta-analysis to ascertain whether ICG-guided laparoscopic hepatectomy yields a higher incidence of complete tumor eradication (R0) resections.

METHODS

The search encompassed databases such as PubMed, Cochrane Library database, Scopus, ScienceDirect, and Ovid in April 2024, in strict adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies involving patients with malignant liver lesions who underwent ICG-guided laparoscopic hepatectomy and reported R0 resection outcomes were eligible for inclusion in this review.

RESULTS

In a total of seven studies, involving 598 patients, were included in the meta-analysis. The ICG demonstrated a significantly elevated R0 resection rate compared to the non-ICG group [98.6% (359/364) vs. 93.1% (339/364), odds ratio (OR) = 3.76, 95% confidence intervals (CI) 1.45-9.51, P = 0.005]. Notably, no heterogeneity was observed (I2 = 0%, P = 0.5). However, the subtype analysis focusing on hepatocellular carcinoma [98.2% (165/168) vs. 93.6% (161/172), OR = 3.34, 95% CI 0.94-11.91, P = 0.06) and the evaluation of margin distance (4.96 ± 2.41 vs. 2.79 ± 1.92 millimeters, weighted mean difference = 1.26, 95% CI -1.8-4.32, P = 0.42) revealed no apparent differences. Additionally, the incidence of overall postoperative complications was comparable between both groups, 27.6% (66/239) in the ICG group and 25.4% (75/295) in the non-ICG group (OR = 0.96, 95% CI 0.53-1.76, P = 0.9). No disparities were identified in operative time, intraoperative blood loss, postoperative blood transfusion, and length of hospital stay after the surgery.

CONCLUSIONS

The implementation of ICG-guided laparoscopic hepatectomy can be undertaken with confidence, as it does not compromise either intraoperative or postoperative events. Furthermore, the ICG-guided approach is beneficial to achieving a complete eradication of the tumor during hepatic resection.

TRIAL REGISTRATION

PROSPERO registration number CRD42023446440.

Development of Polymethine Dyes for NIR-II Fluorescence Imaging and Therapy

Fluorescence imaging in the second near-infrared window (NIR-II) is burgeoning because of its higher imaging fidelity in monitoring physiological and pathological processes than clinical visible/the second near-infrared window fluorescence imaging. Notably, the imaging fidelity is heavily dependent on fluorescence agents. So far, indocyanine green, one of the polymethine dyes, with good biocompatibility and renal clearance is the only dye approved by the Food and Drug Administration, but it shows relatively low NIR-II brightness. Importantly, tremendous efforts are devoted to synthesizing polymethine dyes for imaging preclinically and clinically. They have shown feasibility in the customization of structure and properties to fulfill various needs in imaging and therapy. Herein, a timely update on NIR-II polymethine dyes, with a special focus on molecular design strategies for fluorescent, photoacoustic, and multimodal imaging, is offered. Furthermore, the progress of polymethine dyes in sensing pathological biomarkers and even reporting drug release is illustrated. Moreover, the NIR-II fluorescence imaging-guided therapies with polymethine dyes are summarized regarding chemo-, photothermal, photodynamic, and multimodal approaches. In addition, artificial intelligence is pointed out for its potential to expedite dye development. This comprehensive review will inspire interest among a wide audience and offer a handbook for people with an interest in NIR-II polymethine dyes.

[Indocyanine green in liver tumor resection]

Primary liver cancer and colorectal cancer liver metastases are among the leading causes of cancer-related mortality worldwide. Surgery is one of the main methods of treatment to achieve the best results in overall and recurrence-free survival. The main objectives in this surgery are preoperative planning, assessment of functional viability of liver parenchyma and total resection with low complication rate. Post-resection liver failure is one of the most formidable and often fatal complication following functional failure of liver remnant. Thus, preoperative assessment of liver functional reserves is a necessary step for adequate selection of patients and safe surgery. Passive liver tests, such as biochemical parameters or clinical scales, do not accurately reflect the actual functional component of liver parenchyma. The most accurate method is dynamic quantitative test of liver, such as indocyanine green clearance. The authors discuss the practical aspects of preoperative assessment of liver functional reserves using indocyanine green, as well as the concept and technical foundations of fluorescent imaging in hepatobiliary surgery.

Natural Course of Pachychoroid Pigment Epitheliopathy

PURPOSE

To investigate the natural course of pachychoroid pigment epitheliopathy (PPE).

DESIGN

A retrospective cohort study.

SUBJECTS

From the Kyoto central serous chorioretinopathy (CSC) cohort consisting of 548 patients with CSC as of September 2020, we included consecutive unilateral patients with acute or chronic CSC between January 2013 and December 2016.

METHODS

All patients underwent complete ophthalmic examination, including multimodal imaging such as fundus autofluorescence, spectral-domain optical coherence tomography, and fluorescein angiography/indocyanine green angiography and/or optimal coherence tomography angiography. The fellow eyes of eyes diagnosed with CSC were screened for PPE, and their natural course was evaluated. We also evaluated the association of ARMS2 rs10490924, CFH rs800292, TNFRSF10A rs13278062, and GATA5 rs6061548 genotypes with the natural course.

MAIN OUTCOME MEASURES

Incidence of CSC, pachychoroid neovasculopathy, and pachychoroid geographic atrophy (GA).

RESULTS

In total, 165 patients with unilateral CSC (mean age, 55.7 ± 12.6 years; female, 22.4%) were included from the Kyoto CSC cohort. Among them, 148 (89.7%) were diagnosed as having PPE in their non-CSC eye. Survival analysis revealed that 16.8% of PPE eyes developed CSC during the 6-year follow up, whereas non-PPE eyes did not. Although genetic factors did not have significant association with CSC development (P > 0.05, log-rank test), choroidal vascular hyperpermeability (CVH) and subfoveal choroidal thickness (SFCT) were significantly associated with CSC incidence (P = 0.001, log-rank test). Survival analysis showed that eyes without CVH and eyes with SFCT < 300 μm did not develop CSC during the 6-year follow-up. Pachychoroid neovasculopathy developed in only 1 eye with PPE during a follow-up of 46.4 months. Pachychoroid GA did not develop in any of the studied eyes.

CONCLUSIONS

This study revealed a natural history of PPE in a relatively large Japanese cohort. Choroidal vascular hyperpermeability and SFCT were significant risk factors for the development of CSC in PPE eyes. Although the current results cannot be generalized for all eyes with PPE, these findings present an important clinical implication.

A Narrative Review of the Usefulness of Indocyanine Green Fluorescence Angiography for Perfusion Assessment in Colorectal Surgery

Anastomotic leakage is one of the most dreaded complications of colorectal surgery and is strongly associated with tissue perfusion. Indocyanine green fluorescence angiography (ICG-FA) using indocyanine green and near-infrared systems is an innovative technique that allows the visualization of anastomotic perfusion. Based on this information on tissue perfusion status, surgeons will be able to clearly identify colorectal segments with good blood flow for safer colorectal anastomosis. The results of several clinical trials indicate that ICG-FA may reduce the risk of AL in colorectal resection; however, the level of evidence is not high, as several other studies have failed to demonstrate a reduction in the risk of AL. Several large-scale RCTs are currently underway, and their results will determine whether ICG-FA is, indeed, useful. The major limitation of the current ICG-FA evaluation method, however, is that it is subjective and based on visual assessment by the surgeon. To complement this, the utility of objective evaluation methods for fluorescence using quantitative parameters is being investigated. Promising results have been reported from several clinical trials, but all trials are preliminary owing to their small sample size and lack of standardized protocols for quantitative evaluation. Therefore, appropriately standardized, high-quality, large-scale studies are warranted.

Effectiveness of Reduced-fluence Photodynamic Therapy for Chronic Central Serous Chorioretinopathy: A Propensity Score Analysis

Purpose

To investigate the 2-year effectiveness of reduced-fluence photodynamic therapy (rf-PDT) for chronic central serous chorioretinopathy (cCSC).

Design

Retrospective cohort study.

Participants

A total of 223 consecutive patients with newly diagnosed cCSC with active serous retinal detachment (SRD) were included from May 2007 to June 2017 and followed up for at least 2 years. Patients who underwent ocular treatment other than cataract surgery before the beginning of recruitment and those who had macular neovascularization at baseline were excluded.

Methods

All patients underwent a comprehensive ophthalmic evaluation, including measurements of best-corrected visual acuity (BCVA), slit-lamp examination, dilated fundus examination, color fundus photography, fundus autofluorescence, fluorescein angiography, indocyanine green angiography, and spectral-domain OCT. An inverse probability of treatment weighting (IPTW) methodology was applied to balance 18 baseline characteristics between patients who received rf-PDT (rf-PDT group) and those who did not receive treatment (controls). Inverse probability of treatment weighting survival analysis and regression were performed.

Main Outcome Measures

The proportion of patients whose BCVA at 24 months was the same or improved compared with the baseline visual acuity (VA) (VA maintenance rate).

Results

A total of 155 eyes (rf-PDT group: 74; controls: 81) were analyzed. The patients' backgrounds were well balanced after IPTW with standardized differences of < 0.10. An IPTW regression analysis revealed that the VA maintenance rate was significantly higher in the rf-PDT group than in the controls (93.6% vs. 70.9%, P < 0.001, 12 months; 85.7% vs. 69.8%, P = 0.019, 24 months). The rf-PDT group tended to show better VA improvement, but was not statistically significant (-0.06 vs. -0.008, P = 0.07, 12 months; -0.06 vs. -0.03, P = 0.32, 24 months). An IPTW Cox regression showed a significantly higher rate of complete SRD remission in the rf-PDT group (hazard ratio, 5.05; 95% confidence interval, 3.24-7.89; P < 0.001).

Conclusions

The study suggests the beneficial effect of rf-PDT for cCSC for both VA maintenance and higher proportion of complete SRD remission in the clinical setting.

Assessing the development status of intraoperative fluorescence imaging for perfusion assessments, using the IDEAL framework

Objectives

Intraoperative fluorescence imaging is currently used in a variety of surgical fields for four main purposes: assessing tissue perfusion; identifying/localizing cancer; mapping lymphatic systems; and visualizing anatomy. To establish evidence-based guidance for research and practice, understanding the state of research on fluorescence imaging in different surgical fields is needed. We evaluated the evidence on fluorescence imaging for perfusion assessments using the Idea, Development, Exploration, Assessment, Long Term Study (IDEAL) framework, which was designed for describing the stages of innovation in surgery and other interventional procedures.

Design

Narrative literature review with analysis of IDEAL stage of each field of study.

Setting

All publications on intraoperative fluorescence imaging for perfusion assessments reported in PubMed through 2019 were identified for six surgical procedures: coronary artery bypass grafting (CABG), upper gastrointestinal (GI) surgery, colorectal surgery, solid organ transplantation, reconstructive surgery, and cerebral aneurysm surgery.

Main outcome measures

The IDEAL stage of research evidence was determined for each specialty field using a previously described approach.

Results

196 articles (15 003 cases) were selected for analysis. Current status of research evidence was determined to be IDEAL Stage 2a for upper GI and transplantation surgery, IDEAL 2b for CABG, colorectal and cerebral aneurysm surgery, and IDEAL Stage 3 for reconstructive surgery. Using the technique resulted in a high (up to 50%) rate of revisions among surgical procedures, but its efficacy improving postoperative outcomes has not yet been demonstrated by randomized controlled trials in any discipline. Only one possible adverse reaction to intravenous indocyanine green was reported.

Conclusions

Using fluorescence imaging intraoperatively to assess perfusion is feasible and appears useful for surgical decision making across a range of disciplines. Identifying the IDEAL stage of current research knowledge aids in planning further studies to establish the potential for patient benefit.

Tumor visualization and fluorescence angiography with indocyanine green (ICG) in laparoscopic and robotic hepatobiliary surgery - valuation of early adopters from Germany

Objectives

Indocyanine green (ICG) is a fluorescent dye which was initially used for liver functional assessment. Moreover, it is of value for intraoperative visualization of liver segments and bile ducts or primary and secondary liver tumors. Especially in minimally invasive liver surgery, this is essential to enhance the precision of anatomical guided surgery and oncological quality. As early adopters of ICG implementation into laparoscopic and robotic-assisted liver surgery in Germany, we summarize the current recommendations and share our experiences.

Methods

Actual strategies for ICG application in minimally invasive liver surgery were evaluated and summarized during a review of the literature. Experiences in patients who underwent laparoscopic or robotic-assisted liver surgery with intraoperative ICG staining between 2018 and 2020 from the Magdeburg registry for minimally invasive liver surgery (MD-MILS) were evaluated and the data were analyzed retrospectively.

Results

ICG can be used to identify anatomical liver segments by fluorescence angiography via direct or indirect tissue staining. Fluorescence cholangiography visualizes the intra- and extrahepatic bile ducts. Primary and secondary liver tumors can be identified with a sensitivity of 69-100%. For this 0.5 mg/kg body weight ICG must be applicated intravenously 2-14 days prior to surgery. Within the MD-MILS we identified 18 patients which received ICG for intraoperative tumor staining of hepatocellular carcinoma (HCC), cholangiocarcinoma, peritoneal HCC metastases, adenoma, or colorectal liver metastases. The sensitivity for tumor staining was 100%. In 27.8% additional liver tumors were identified by ICG fluorescence. In 39% a false positive signal could be detected. This occurred mainly in cirrhotic livers.

Conclusions

ICG staining is a simple and useful tool to assess individual hepatic anatomy or to detect tumors during minimally invasive liver surgery. It may enhance surgical precision and improve oncological quality. False-positive detection rates of liver tumors can be reduced by respecting the tumor entity and liver functional impairments.

Effect of indocyanine green fluorescence angiography on preventing anastomotic leakage after colorectal surgery: a meta-analysis

Anastomotic leakage (AL) is a serious but not uncommon complication after colorectal surgery. We conducted this study to evaluate the effect of routine indocyanine green fluorescence angiography (ICG-FA) on reducing the AL rate after colorectal surgery. We identified all research articles about colorectal surgery using ICG-FA, published in the PubMed, EMBASE, and Cochrane Library databases from the date of database establishment to May 2020. Revman 5.3 was used for statistical analysis. We analyzed 22 controlled studies and 7 non-controlled studies on ICG-FA, including 6312 patients. The controlled studies included 2354 patients in the ICG group and 3522 patients in the non-ICG group. Meta-analysis showed that ICG-FA reduced the AL rate after colorectal surgery significantly (RR = 0.39; 95% CI 0.30-0.50; P < 0.00001). However, patients whose resection line was changed based on the fluorescence angiography had a higher AL rate than those whose resection line was not changed (OR = 5.37; 95% CI 2.67-10.81; P < 0.00001). The overall complication rate, severe complication rate, and reoperation rate in the ICG group were significantly lower than those in the non-ICG group (RR = 0.79, 95% CI 0.67-0.92, P = 0.002; RR = 0.67, 95% CI 0.47-0.96, P = 0.03; RR = 0.53, 95% CI 0.29-0.96, P = 0.04, respectively), whereas the postoperative ileus rate was significantly higher in the ICG group than in the non-ICG group (RR = 1.65; 95% CI 1.09-2.50; P = 0.02), especially in Western countries (RR = 1.6; 95% CI 1.04-2.47; P = 0.03).ICG-FA may reduce the AL rate after colorectal surgery, but ICG-FA group patients with transection line change for insufficient blood perfusion to the anastomotic stoma after evaluation had a higher AL rate than those without transection line change. Therefore, ICG-FA can help to identify patients at high risk of AL and intercept its occurrence. Moreover, ICG-FA may reduce the overall complication rate, severe complication rate, and reoperation rate, but induce postoperative ileus. High-quality randomized-controlled trials with a placebo control are needed to further evaluate the effectiveness and safety of ICG-FA.

Central serous chorioretinopathy: An update on risk factors, pathophysiology and imaging modalities

Central serous chorioretinopathy (CSC) is a common form of vision loss, typically seen in working-age men. The pathophysiology behind CSC still eludes us, however significant advances have been made in understanding this disease over the last decade using information from genetic and cell-based studies and imaging modalities. This review aims to give an overview of the current pathophysiology hypotheses surrounding CSC in addition to future directions in cellular work from human induced pluripotent stem cell derived choroidal endothelial cells from CSC patients. Furthermore, this review will provide the reader with an update on the clinical aspects of CSC including risk factors, diagnostic challenges and findings from multimodal imaging.

ACUTE EFFECT OF CAFFEINE ON MACULAR MICROCIRCULATION IN HEALTHY SUBJECTS: An Optical Coherence Tomography Angiography Study

PURPOSE

To evaluate the acute effects of caffeine on macular microvasculature using quantitative optical coherence tomography angiography analysis.

METHODS

Fifty-two healthy subjects aged 24 to 48 years were randomly divided into 2 groups: a control group, which received placebo, and a study group, which was subjected to caffeine. All participants underwent optical coherence tomography angiography at baseline and 1 hour after 200-mg oral caffeine intake in the study group and after oral placebo in the control group. Macular flow area, macular vessel density, and foveal avascular zone (FAZ) area were analyzed in both the groups.

RESULTS

The study group consisted of 14 men and 12 women with a mean age of 40.6 ± 8.9 years. The mean age of control group was 39.5 ± 9.4 years, which consisted of 13 men and 13 women. Baseline macular flow area, vessel density, and FAZ area measurements of the study and control groups showed no significant difference (P > 0.05). Oral caffeine intake caused a significant reduction in macular flow area (superficial, deep, and choriocapillaris) and vessel density (P < 0.05). However, there was no statistically significant difference in FAZ area after caffeine intake when compared with baseline measurements (P = 0.063).

CONCLUSION

We found a significant decrease in macular flow area (superficial, deep, and choriocapillaris) and vessel density after caffeine intake. Our findings are consistent with previous studies using other techniques. We believe that the results of this preliminary study will be useful in future studies about this topic.

Optical Coherence Tomography of Choroid in Common Neurological Diseases

The choroid is involved directly and indirectly in many pathological conditions such as age-related macular degeneration, myopia-related chorioretinal atrophy and central serous chorioretinopathy. Optical coherence tomography (OCT) has gradually become a fundamental part of modern resources in the hands of ophthalmologists. The enhanced depth imaging technique and swept-source OCT make a great contribution to conventional in vivo choroid assessment. This review focuses on the most common neurological conditions in which choroid assessment by OCT may provide help in early diagnosis and be used as an interdisciplinary follow-up tool. In order to avoid evaluation biases and misdiagnosis, the main and most common physiological and para-physiological conditions in which the choroid may show alterations are also reviewed.

Fluorescence-Guided Surgery for Hepatoblastoma with Indocyanine Green

Fluorescence-guided surgery with indocyanine green (ICG) for malignant hepatic tumors has been gaining more attention with technical advancements. Since hepatoblastomas (HBs) possess similar features to hepatocellular carcinoma, fluorescence-guided surgery can be used for HBs, as aggressive surgical resection, even for distant metastases of HBs, often contributes positively to R0 (complete) resection and subsequent patient survival. Despite a few caveats, fluorescence-guided surgery allows for the more sensitive identification of lesions that may go undetected by conventional imaging or be invisible macroscopically. This leads to precise resection of distant metastatic tumors as well as primary liver tumors.

Impact of indocyanine green-fluorescence imaging on distal pancreatectomy with celiac axis resection combined with reconstruction of the left gastric artery

BACKGROUND

We previously reported the usefulness of distal pancreatectomy with celiac axis resection (DP-CAR) with left gastric artery (LGA) reconstruction to prevent ischemic gastropathy. To evaluate the reconstruction quality, we performed intraoperative angiography with indocyanine green (ICG)-fluorescence imaging.

METHODS

21 consecutive patients planned for DP-CAR with LGA reconstruction were enrolled in this prospective, exploratory single-arm study from 2014 to 2017. After LGA reconstruction, intraoperative angiography revealed continuous arterial flow passing through the anastomotic sites and gradually increasing tissue perfusion in the stomach.

RESULTS

Three patients were excluded. Among the remaining 18 patients, we obtained good flow in 11 patients and poor flow in 7 patients after initial LGA reconstruction. Among the seven patients with poor flow, five underwent LGA re-anastomosis, three recovered good flow. The incidence of grade B/C DGE was 14% (2/14) in the finally good flow group and 75% (3/4) in the poor flow group (p = 0.019). Ischemic gastropathy occurred in two patients (50%) in the poor flow group (p = 0.039), including one with a gastric perforation.

DISCUSSION

Our data show that intraoperative angiography with ICG-fluorescence imaging can evaluate the reconstruction quality, thus contributing to improvements in the short-term outcome of DP-CAR with LGA reconstruction.

Fluorescence guided surgery in liver tumors: applications and advantages

The use of fluorescence-guided surgery for benign and malignant hepatobiliary (HPB) neoplasms has significantly increased and improved imaging methods creating new interesting perspectives. A major challenge in HPB surgery is performing radical resection with maximal preservation of the liver parenchyma and obtaining a low rate of complications. Despite the developments, visual inspection, palpation, and intraoperative ultrasound remain the most utilized tools during surgery today. In laparoscopic and robotic HPB surgery palpation is not possible. Fluorescence imaging enables identification of subcapsular liver tumors through accumulation of indocyanine green (ICG), after preoperative intravenous injection, in cancerous tissues of hepatocellular carcinoma and in noncancerous hepatic parenchyma, around intrahepatic cholangiocarcinoma and liver metastases, and it can also be used for visualizing extrahepatic bile duct anatomy and hepatic segmental borders, increasing the accuracy and the easiness of open and minimally invasive hepatectomy. (www.actabiomedica.it)

Submacular Hemorrhage: Visual Outcomes and Prognostic Factors

PURPOSE

To describe causes, visual outcomes, and prognostic factors in patients with submacular hemorrhage (SMH).

DESIGN

Retrospective case review.

METHODS

We performed a retrospective review of SMH with a size of at least 1 disc diameter. SMH causes were classified into 3 groups: 1) neovascular age-related macular degeneration (nAMD), 2) polypoidal choroidal vasculopathy (PCV), and 3) other miscellaneous causes.

RESULTS

Ninety-eight eyes of 98 patients were included. Based on clinical presentation and indocyanine green angiography (ICGA), the diagnoses of PCV (59%), nAMD (31%), and miscellaneous other causes (10%) were made. PCV patients were younger (P = 0.005) and had larger SMH size than nAMD patients (P = 0.008). Poor visual outcome [>1.0 logarithm of the minimum angle of resolution (logMAR)] at 6 months was associated with low initial visual acuity (VA; >1.0 logMAR; P = 0.002) and with the diagnosis of nAMD (P = 0.02). In addition, limited visual outcomes were noted for patients older than 65 years and those with persistent SMH for at least 2 months.

CONCLUSIONS

PCV was the most common cause of SMH in Thailand. ICGA represented a valuable tool for the diagnosis. Visual outcomes were limited for patients with nAMD and for patients who presented with poor initial VA.

Choroidal thickness in patients with coronary artery disease

Purpose

To evaluate choroidal thickness (CTh) in patients with coronary artery disease (CAD) compared to healthy controls.

Design

Cross-sectional.

Methods

Setting: Ambulatory clinic of a large city hospital. Patient population: Thirty-four patients had documented CAD, defined as history of >50% obstruction in at least one coronary artery on cardiac catheterization, positive stress test, ST elevation myocardial infarction, or revascularization procedure. Twenty-eight age-matched controls had no self-reported history of CAD or diabetes. Patients with high myopia, dense cataracts, and retinal disease were excluded. Observation procedures: Enhanced depth imaging optical coherence tomography and questionnaire regarding medical and ocular history. Main outcome measures: Subfoveal CTh and CTh 2000 μm superior, inferior, nasal, and temporal to the fovea in the left eye, measured by 2 readers.

Results

CTh was significantly lower in patients with CAD compared to controls at the subfoveal location (252 vs. 303 μm, P = 0.002) and at all 4 cardinal macular locations. The mean difference in CTh between the 2 groups ranged from 46 to 75 μm and was greatest in the inferior location. Within the CAD group, CTh was significantly lower temporally (P = 0.007) and nasally (P<0.001) than subfoveally, consistent with the pattern observed in controls. On multivariate analysis, CAD was negatively associated with subfoveal CTh (P = 0.006) after controlling for diabetes, hypertension, and hypercholesterolemia.

Conclusions and relevance

Patients with CAD have a thinner macular choroid than controls, with preservation of the normal spatial CTh pattern. Decreased CTh might predispose patients with CAD to high-risk phenotypes of age-related macular degeneration such as reticular pseudodrusen and could serve as a potential biomarker of disease in CAD.

Polypoidal Choroidal Vasculopathy with Feeder Vessels: Characteristics, Fellow Eye Findings, and Long-term Treatment Outcomes

PURPOSE

To evaluate the long-term outcomes of anti-vascular endothelial growth factor (VEGF) therapy for polypoidal choroidal vasculopathy (PCV) with feeder vessels and to investigate fellow-eye findings.

METHODS

This retrospective observational study included 14 eyes with treatment-naïve PCV accompanied by feeder vessels that were treated with anti-VEGF monotherapy. The best-corrected visual acuity (BCVA) at baseline was compared with that at the last follow-up. The fellow-eye indocyanine green angiography findings were also analyzed.

RESULTS

The mean follow-up period was 28.1 ± 19.2 months (range, 12 to 60 months). During the follow-up period, 5.9 ± 2.5 anti-VEGF injections were administered. The logarithm of the minimal angle of resolution (logMAR) BCVAs at the time of diagnosis, at 3 months, and at the last follow-up were 0.81 ± 0.49, 0.55 ± 0.44, and 0.71 ± 0.54, respectively. Although the BCVA at the last follow-up was not different from the baseline value (p=0.809), an improvement of ≥0.2 logMAR BCVA was observed in seven eyes (50.0%). In 11 eyes that underwent bilateral indocyanine green angiography at diagnosis, PCV, branching vascular networks, and late geographic hyperfluorescence were noted in two (18.2%), five (45.4%), and three (27.3%) fellow eyes, respectively. During the follow-up period, the development of polypoidal lesions in the fellow eye was observed in three patients.

CONCLUSIONS

In this study, long-term improvement in BCVA was noted in 50% of the included patients who received anti-VEGF monotherapy. A relatively high incidence of pathological findings in the fellow eye and bilateral involvement suggest the need for bilateral examinations.

CHOROIDAL MELANOMA INITIALLY TREATED AS HEMANGIOMA: DIAGNOSTIC AND THERAPEUTIC CONSIDERATIONS

PURPOSE

To describe and analyze cases of circumscribed choroidal melanoma initially treated as circumscribed choroidal hemangioma.

METHODS

A retrospective case series including five eyes of five patients with choroidal melanoma that were originally diagnosed and treated as choroidal hemangioma.

RESULTS

Four men and 1 woman (26-61 years) were included. All patients were white and presented with nonspecific symptoms (visual field defect, decreased visual acuity, and metamorphopsia) and visual acuity ranging from 20/30 to 20/80. Four of the five tumors were yellow and/or orange and one was partially melanotic. All tumors were dome shaped (one bilobed) and had associated subretinal fluid overlying the lesion. Two tumors had high internal reflectivity on standardized A-scan ultrasonography, whereas others had low internal reflectivity. Three tumors were hypofluorescent on early phases of indocyanine green and intrinsic vasculature was also observed in two of these three. Four of five patients who were initially treated by photodynamic therapy did not respond to treatment. However, they did respond to radiation therapy (after revised diagnosis), with documented regression and no evidence of detectable metastasis (mean follow-up 24.2 months).

CONCLUSION

Differentiating between amelanotic melanoma and choroidal hemangioma can be challenging. Relying solely on ophthalmoscopic features can be misleading. Ancillary studies such as indocyanine green and standardized A-scan ultrasonography bring clarity in differentiating circumscribed choroidal hemangioma from choroidal melanoma. Although cytology or histopathology is the only definitive method of establishing the diagnosis, careful emphasis on key diagnostic features can obviate the need for diagnostic fine-needle aspiration biopsy in most cases.

Choroidal thickness profile in healthy Indian children

Purpose:

The purpose was to study choroidal thickness and its profile based on location in healthy Indian children using enhanced depth spectral-domain-optical coherence tomography (SD-OCT).

Methods:

In this cross-sectional observational study 255 eyes of 136 children with no retinal or choroidal disease were consecutively scanned using enhanced depth SD-OCT. Eyes with any ocular disease or axial length (AXL) >25 mm or < 20 mm were excluded. A single observer measured choroidal thickness from the posterior edge of the retinal pigment epithelium to the choroid/sclera junction at 500-microns intervals up to 2500 microns temporal and nasal to the fovea. Generalized estimating equations were used to evaluate the correlation between choroidal thickness at various locations and age, AXL, gender and spherical equivalent (SEq).

Results:

Mean age of the subjects was 11.9 ± 3.4 years (range: 5–18 years). There were 62 Females and 74 males. The mean AXL was 23.55 ± 0.74 mm. Mean subfoveal choroidal thickness was 312.1 ± 45.40 μm. Choroid was found to be thickest subfoveally, then temporally. Age, AXL and SEq showed a significant correlation with choroidal thickness, whereas gender did not affect choroidal thickness.

Conclusion:

Our study provides a valid normative database of choroidal thickness in healthy Indian children. This database could be useful for further studies evaluating choroidal changes in various chorioretinal disorders. Age and AXL are critical factors, which negatively correlated with choroidal thickness.

Detection of Choroidal Neovascularization in Central Serous Chorioretinopathy Using Optical Coherence Tomographic Angiography

Purpose: To demonstrate the detection of choroidal neovascularization (CNV) in clinically diagnosed central serous chorioretinopathy (CSC) by optical coherence tomographic angiography (OCTA). Methods: Seventy-five eyes of 70 patients were included. OCTA was performed on each patient. Two trained readers evaluated the images independently to confirm the diagnosis and identify CNV at the level of the outer retina. Results: All studied eyes presented characteristics consistent with CSC based on eye examination and traditional imaging technologies, including fundus fluorescein angiography, which showed no evidence of CNV. However, OCTA revealed definite abnormal vascularization at the level of the outer retina in 8 eyes (10.7%) of 8 patients (11.4%). Conclusion: This study suggests that in some cases of CSC, OCTA could be an alternative option to detect CNV that is undetectable by other conventional imaging techniques.

Clinical application of indocyanine green-fluorescence imaging during hepatectomy

In hepatobiliary surgery, the fluorescence and bile excretion of indocyanine green (ICG) can be used for real-time visualization of biological structure. Fluorescence cholangiography is used to obtain fluorescence images of the bile ducts following intrabiliary injection of 0.025-0.5 mg/mL ICG or intravenous injection of 2.5 mg ICG. Recently, the latter technique has been used in laparoscopic/robotic cholecystectomy. Intraoperative fluorescence imaging can be used to identify subcapsular hepatic tumors. Primary and secondary hepatic malignancy can be identified by intraoperative fluorescence imaging using preoperative intravenous injection of ICG through biliary excretion disorders that exist in cancerous tissues of hepatocellular carcinoma (HCC) and in non-cancerous hepatic parenchyma around adenocarcinoma foci. Intraoperative fluorescence imaging may help detect tumors to be removed, especially during laparoscopic hepatectomy, in which visual inspection and palpation are limited, compared with open surgery. Fluorescence imaging can also be used to identify hepatic segments. Boundaries of hepatic segments can be visualized following injection of 0.25-2.5 mg/mL ICG into the portal veins or by intravenous injection of 2.5 mg ICG following closure of the proximal portal pedicle toward hepatic regions to be removed. These techniques enable identification of hepatic segments before hepatectomy and during parenchymal transection for anatomic resection. Advances in imaging systems will increase the use of fluorescence imaging as an intraoperative navigation tool that can enhance the safety and accuracy of open and laparoscopic/robotic hepatobiliary surgery.

Comparison of the Clinical Manifestations between Acute Vogt-Koyanagi-Harada Disease and Acute Bilateral Central Serous Chorioretinopathy

Purpose

To compare clinical, angiographic, and optical coherence tomographic characteristics between eyes with acute Vogt-Koyanagi-Harada (VKH) disease and eyes with acute bilateral central serous chorioretinopathy (CSC), and to demonstrate distinguishing features between the two diseases in confusing cases.

Methods

The medical records of 35 patients with VKH disease and 25 patients with bilateral CSC were retrospectively reviewed. Characteristics according to slit-lamp biomicroscopy, ophthalmoscopy, fundus photography, fluorescein angiography, indocyanine green angiography, and spectral-domain optical coherence tomography were compared between the two diseases.

Results

Five of 35 patients (10 of 70 eyes, 14.3%) with VKH disease were initially misdiagnosed as CSC patients, and six of 25 patients (12 of 50 eyes, 24%) with bilateral CSC were initially misdiagnosed as patients with VKH disease. Pigment epithelial detachment in CSC and optic disc hyperemia in VKH disease show the highest positive predictive values of 100% for each disease.

Conclusions

Optic disc hyperemia in VKH disease and pigment epithelial detachment in bilateral CSC are the most specific clinical manifestations of each disease at initial patient presentation.

Feasibility and clinical utility of ultra-widefield indocyanine green angiography

PURPOSE

To evaluate the feasibility and clinical utility of a novel noncontact scanning laser ophthalmoscope-based ultra-widefield indocyanine green angiographic system.

METHODS

Ultra-widefield indocyanine green angiographic images were captured using a modified Optos P200Tx that produced high-resolution images of the choroidal vasculature with up to a 200° field. Ultra-widefield indocyanine green angiography was performed on patients with a variety of retinal conditions to assess utility of this imaging technique for diagnostic purposes and disease treatment monitoring.

RESULTS

Ultra-widefield indocyanine green angiography was performed on 138 eyes of 69 patients. Mean age was 58 ± 16.9 years (range, 24-85 years). The most common ocular pathologies imaged included central serous chorioretinopathy (24 eyes), uveitis (various subtypes, 16 eyes), age-related macular degeneration (12 eyes), and polypoidal choroidal vasculopathy (4 eyes). In all eyes evaluated with ultra-widefield indocyanine green angiography, high-resolution images of choroidal and retinal circulation were obtained with sufficient detail out to 200° of the fundus.

CONCLUSION

In this series of 138 eyes, scanning laser ophthalmoscope-based ultra-widefield indocyanine green angiography was clinically practical and provided detailed images of both the central and peripheral choroidal circulation. Future studies are needed to refine the clinical value of this imaging modality and the significance of peripheral choroidal vascular changes in the diagnosis, monitoring, and treatment of ocular diseases.

Identification of Underlying Causes of Spontaneous Submacular Hemorrhage by Indocyanine Green Angiography

Purpose: To investigate the causes of acute spontaneous submacular hemorrhage with indocyanine green angiography (ICGA). Methods: Retrospective observation case series. A total of 51 eyes from 51 patients with newly developed spontaneous submacular hemorrhage were enrolled. Best-corrected visual acuity (BCVA), fundus photography, fluorescein angiography, spectral domain optical coherence tomography (OCT), and ICGA at baseline were analyzed. The extent of hemorrhage using fundus photography, height of hemorrhage, and central foveal thickness measured by OCT was analyzed to compare the diagnostic and nondiagnostic groups. Results: The mean logarithm of the minimum angle of resolution (logMAR) BCVA at presentation was 1.21 ± 0.74 (Snellen equivalent, 20/324); the mean follow-up period was 23.9 ± 23.9 months. The cause of submacular hemorrhage was diagnosed in 43 of 51 eyes (84.3%) based on ICGA at presentation. The initial diagnoses were correct in 93% of eyes. In 3 cases, the initial diagnosis of age-related macular degeneration (AMD) was changed to polypoidal choroidal vasculopathy (PCV) based on follow-up ICGA. The central foveal thickness was significantly greater in the nondiagnostic group (1,102.4 vs. 666.7 μm, respectively; p = 0.008). The most common cause of submacular hemorrhage was neovascular AMD (52.9%), followed by PCV (37.3%), macroaneurysm (5.9%), and lacquer crack (3.9%). The mean final visual acuity was generally worse in patients with submacular hemorrhage with typical AMD (visual acuity 20/618) or PCV (visual acuity 20/240) compared to that in patients with retinal macroaneurysm (visual acuity 20/100) or lacquer crack (visual acuity 20/72). Conclusions: ICGA at initial presentation helps identify causes of submacular hemorrhage, allowing differential treatment approaches that may improve outcomes and safety.

Distribution and determinants of choroidal thickness and volume using automated segmentation software in a population-based study

PURPOSE

To objectively quantify choroidal thickness and choroidal volume using fully automated choroidal segmentation software applied to images obtained from enhanced depth imaging spectral-domain optical coherence tomography (EDI SD OCT) in a population-based study; and evaluate the ocular and systemic determinants of choroidal thickness and choroidal volume.

DESIGN

Prospective cross-sectional study.

METHODS

Participants ranging in age from 45 to 85 years were recruited from the Singapore Malay Eye Study-2 (SiMES-2), a follow-up population-based study. All participants (n = 540) underwent a detailed ophthalmic examination, including EDI SD OCT for measurements of thickness and volume of the choroid.

RESULTS

The intrasession repeatability of choroidal thickness at 5 measured horizontal locations and macular choroidal volume using automated choroidal segmentation software was excellent (intraclass correlation coefficient, 0.97-0.99). Choroid was significantly thicker under the fovea (242.28 ± 97.58 μm), followed by 3 mm temporal (207.65 ± 80.98 μm), and was thinnest at 3 mm nasal (142.44 ± 79.19 μm) location. The mean choroidal volume at central macular region (within a circle of 1 mm diameter) was 0.185 ± 0.69 mm(3). Among the range of ocular and systemic factors studied, age, sex, and axial length were the only significant predictors of choroidal thickness and choroidal volume (all P < .05).

CONCLUSIONS

Using a new automated choroidal segmentation software, we provide fast, reliable, and objective measurements of choroidal thickness and volume in a population-based sample. Male sex, younger age, and shorter axial length are the factors independently associated with thicker choroid and larger choroidal volume. These factors should be taken into consideration when interpreting EDI SD OCT-based choroidal thickness measurements in clinics.

Effect of ranibizumab on high-speed indocyanine green angiography and minimum intensity projection optical coherence tomography findings in neovascular age-related macular degeneration

PURPOSE

The purpose of this 1-year prospective study was to investigate how induction/pro re nata ranibizumab intravitreal treatment of eyes with neovascular age-related macular degeneration affects the anatomy of choroidal neovascularization (CNV) and the overlying outer retinal tissue.

METHODS

High-speed indocyanine green (HS-ICG) angiography measurements provided quantification of the CNV size in 60 patients followed for 1 year. Minimum intensity projection optical coherence tomography (MinIP OCT), a novel algorithm assessing minimum optical intensity between the internal limiting membrane and retinal pigment epithelium, measured the area of outer retinal disruption overlying the CNV. Fluorescein angiography was also assessed to evaluate late retinal leakage.

RESULTS

After 1 year, the mean area of CNV measured with indocyanine green angiography decreased by 5.8%. The mean area of MinIP OCT of outer retinal disruption overlying the CNV decreased by 4.2%. Mean area of fluorescein angiography leakage decreased by 6.3%. Both the area of outer retinal disruption measured with MinIP OCT and the area of leakage on fluorescein angiography typically exceeded the area of CNV on indocyanine green angiography at baseline and 1 year.

CONCLUSION

Choroidal neovascularization treated with induction/pro re nata intravitreal ranibizumab for 1 year essentially remained static. Minimum intensity projection optical coherence tomography suggests that the area of outer retinal disruption overlying the CNV may be greater than the CNV itself and often correlates with the leakage area on fluorescein angiography. Additionally, there was minimal change in the area of outer retinal disruption on MinIP OCT even when fluid resolved. Measurements of the extent of CNV lesions based on indocyanine green angiography and MinIP OCT may provide useful outcome variables to help assess the CNV complex longitudinally and warrant further validation.

Choroidal imaging: A review

Being the most vascular tissue of the eye, importance of the choroid has been very well established in various retinal and chorio-retinal diseases. Understanding of the choroidal structures has improved significantly since the evolution of enhanced depth imaging. Quantitative assessment of choroidal measurements has been found to be reproducible using different devices. This review article describes factors affecting choroidal thickness and choroidal changes in several diseases and reports its clinical importance. Evaluation of choroid would provide insight into the pathogenesis, treatment planning and follow up in chorioretinal diseases.

Detecting abnormalities in choroidal vasculature in a mouse model of age-related macular degeneration by time-course indocyanine green angiography

Indocyanine Green Angiography (or ICGA) is a technique performed by ophthalmologists to diagnose abnormalities of the choroidal and retinal vasculature of various eye diseases such as age-related macular degeneration (AMD). ICGA is especially useful to image the posterior choroidal vasculature of the eye due to its capability of penetrating through the pigmented layer with its infrared spectrum. ICGA time course can be divided into early, middle, and late phases. The three phases provide valuable information on the pathology of eye problems. Although time-course ICGA by intravenous (IV) injection is widely used in the clinic for the diagnosis and management of choroid problems, ICGA by intraperitoneal injection (IP) is commonly used in animal research. Here we demonstrated the technique to obtain high-resolution ICGA time-course images in mice by tail-vein injection and confocal scanning laser ophthalmoscopy. We used this technique to image the choroidal lesions in a mouse model of age-related macular degeneration. Although it is much easier to introduce ICG to the mouse vasculature by IP, our data indicate that it is difficult to obtain reproducible ICGA time course images by IP-ICGA. In contrast, ICGA via tail vein injection provides high quality ICGA time-course images comparable to human studies. In addition, we showed that ICGA performed on albino mice gives clearer pictures of choroidal vessels than that performed on pigmented mice. We suggest that time-course IV-ICGA should become a standard practice in AMD research based on animal models.

Indocyanine green fluorescence imaging in the surgical management of liver cancers: current facts and future implications

Imaging detection of liver cancers and identification of the bile ducts during surgery, based on the fluorescence properties of indocyanine green, has recently been developed in liver surgery. The principle of this imaging technique relies on the intravenous administration of indocyanine green before surgery and the illumination of the surface of the liver by an infrared camera that simultaneously induces and collects the fluorescence. Detection by fluorescence is based on the contrast between the (fluorescent) tumoral or peri-tumoral tissues and the healthy (non-fluorescent) liver. Results suggest that indocyanine green fluorescence imaging is capable of identification of new liver cancers and enables the characterization of known hepatic lesions in real time during liver resection. The purpose of this paper is to present the fundamental principles of fluorescence imaging detection, to describe successively the practical and technical aspects of its use and the appearance of hepatic lesions in fluorescence, and to expose the diagnostic and therapeutic perspectives of this innovative imaging technique in liver surgery.

Mechanistic background and clinical applications of indocyanine green fluorescence imaging of hepatocellular carcinoma

BACKGROUND

Although clinical applications of intraoperative fluorescence imaging of liver cancer using indocyanine green (ICG) have begun, the mechanistic background of ICG accumulation in the cancerous tissues remains unclear.

METHODS

In 170 patients with hepatocellular carcinoma cells (HCC), the liver surfaces and resected specimens were intraoperatively examined by using a near-infrared fluorescence imaging system after preoperative administration of ICG (0.5 mg/kg i.v.). Microscopic examinations, gene expression profile analysis, and immunohistochemical staining were performed for HCCs, which showed ICG fluorescence in the cancerous tissues (cancerous-type fluorescence), and HCCs showed fluorescence only in the surrounding non-cancerous liver parenchyma (rim-type fluorescence).

RESULTS

ICG fluorescence imaging enabled identification of 273 of 276 (99%) HCCs in the resected specimens. HCCs showed that cancerous-type fluorescence was associated with higher cancer cell differentiation as compared with rim-type HCCs (P < 0.001). Fluorescence microscopy identified the presence of ICG in the canalicular side of the cancer cell cytoplasm, and pseudoglands of the HCCs showed a cancerous-type fluorescence pattern. The ratio of the gene and protein expression levels in the cancerous to non-cancerous tissues for Na(+)/taurocholate cotransporting polypeptide (NTCP) and organic anion-transporting polypeptide 8 (OATP8), which are associated with portal uptake of ICG by hepatocytes that tended to be higher in the HCCs that showed cancerous-type fluorescence than in those that showed rim-type fluorescence.

CONCLUSIONS

Preserved portal uptake of ICG in differentiated HCC cells by NTCP and OATP8 with concomitant biliary excretion disorders causes accumulation of ICG in the cancerous tissues after preoperative intravenous administration. This enables highly sensitive identification of HCC by intraoperative ICG fluorescence imaging.

Indocyanine green angiography in posterior uveitis

Literature review for indocyanine green angiography and evaluate the role of indocyanine green angiogram (ICGA) in patients with posterior uveitis seen at a tertiary referral eye care centre. Detailed review of the literature on ICGA was performed. Retrospective review of medical records of patients with posterior uveitis and dual fundus and ICGA was done after institutional board approval. Eighteen patients (26 eyes) had serpiginous choroiditis out of which 12 patients had active choroiditis and six patients had healed choroiditis, six patients (12 eyes) had ampiginous choroiditis, six patients (12 eyes) had acute multifocal posterior placoid pigment epitheliopathy, eight patients (10 eyes) had multifocal choroiditis, four patients (eight eyes) had presumed ocular histoplasmosis syndrome, four patients (eight eyes) had presumed tuberculous choroiditis, two patients (four eyes) had multiple evanescent white dot syndrome and two patients (four eyes) had Vogt Koyanagi Harada (VKH) syndrome. The most characteristic feature noted on ICGA was the presence of different patterns of hypofluorescent dark spots, which were present at different stages of the angiogram. ICGA provides the clinician with a powerful adjunctive tool in choroidal inflammatory disorders. It is not meant to replace already proven modalities such as the fluorescein angiography, but it can provide additional information that is useful in establishing a more definitive diagnosis in inflammatory chorioretinal diseases associated with multiple spots. It still needs to be determined if ICGA can prove to be a follow up parameter to evaluate disease progression.

Acute syphilitic posterior placoid chorioretinitis: report of a case series and comprehensive review of the literature

PURPOSE

To describe the clinical and angiographic features of a series of patients with acute syphilitic posterior placoid chorioretinitis (ASPPC) in the context of previously published cases.

METHODS

A retrospective, noncomparative, multicenter chart review was performed on 16 patients with active ASPPC. Positive serologic tests supported the diagnosis in all patients. Color and red-free photographs as well as fluorescein angiography were obtained in each case. Indocyanine green angiography, optical coherence tomography, and fundus autofluorescence were performed on selected patients. A total of 44 previously published cases of ASPPC were identified using both a Medline Search and references listed in articles identified.

RESULTS

Ocular involvement was bilateral in 9 of our 16 patients (56.3%). The mean and median ages at presentation were 40 and 38 years, respectively (range 28-57 years). Nine patients (56.3%) were human immunodeficiency virus positive, with most recent CD4 cell counts ranging from 160 cells/μL to 450 cells/μL and a median CD4 cell count of 250 cells/μL. Seven of 16 patients (43.8%) had a history of mucocutaneous manifestations of secondary syphilis, whereas 4 (25.0%) had evidence of neurosyphilis. Anterior chamber and/or vitreous inflammation was evident in 13 patients (81.3%). Fifteen of 16 patients had positive venereal disease research laboratory or rapid plasma regain titers, and 13 of 13 tested patients had a positive serum fluorescent treponemal antibody absorption. The initial vision in the 25 affected eyes ranged from 20/20 to counting fingers, with a median of 20/80. In all patients, posterior segment examination in the involved eyes revealed a large, yellowish, placoid, outer retinal lesion. Fluorescein angiography showed progressive hyperfluorescence in the area of the lesion, often with scattered focal hypofluorescence, or leopard spotting. Inflammation subsided, the yellowish lesions resolved, and vision improved shortly after antibiotic therapy in 20 of 25 affected eyes. Visual acuity at last visit ranged from 20/20 to 20/150, with a median final vision of 20/25. A review of the literature revealed 44 previously reported cases of ASPPC. Shared demographic, clinical, and angiographic features were summarized.

CONCLUSION

Acute syphilitic posterior placoid chorioretinitis is an uncommon but clinically and angiographically distinct manifestation of ocular syphilis. All patients with characteristic clinical and angiographic findings of ASPPC should be tested for both neurosyphilis and human immunodeficiency virus coinfection. Vision recovery typically followed completion of appropriate antibiotic therapy.

Changes in choroidal thickness and optical axial length accompanying intraocular pressure increase

PURPOSE

To measure changes in choroidal thickness (CT), retinal thickness (RT), and axial length (AL) accompanying intraocular pressure (IOP) increase and to investigate the changes in axial eye dimensions induced by IOP increase.

METHODS

Thirty-four eyes of 34 patients undergoing a diagnostic provocative test for primary angle closure (PAC). Patients with other macular diseases were excluded. Patients underwent the darkroom prone provocative test (DR-PPT) for 1 h. We measured CT and RT at the fovea by optical coherence tomography with the enhanced depth imaging method and AL with noncontact, partial coherence laser interferometry before and after the DR-PPT.

RESULTS

There was a statistically significant increase in the mean (SD) IOP of 7.3 (9.2) mmHg and the mean (SD) AL of 0.06 (0.12) mm after the DR-PPT (P < 0.001 and P = 0.014, respectively). There was a statistically significant decrease in the mean (SD) subfoveal CT of 30.0 (36.8) μm (P < 0.001), while there was no significant change in the mean foveal RT. The change in subfoveal CT was negatively correlated with the changes in IOP (r = -0.71, P < 0.001) and AL (r = -0.54, P = 0.004).

CONCLUSIONS

In eyes suspected of having PAC, acutely increased IOP accompanies choroid thinning and corresponding elongation of the optical axis.

Clinical application of fluorescence imaging of liver cancer using indocyanine green

Recently, fluorescence imaging using indocyanine green (ICG) has been applied to hepatobiliary surgery, not only to visualize the bile ducts, but also to identify liver cancer during surgery. In this technique, ICG is administered intravenously at a dose of 0.5 mg/kg body weight for routine liver function testing before surgery. Intraoperatively, liver cancer can be readily identified by fluorescence imaging on the liver surface before resection and on the cut surface of the resected specimen. This is achieved by visualizing fluorescence from the area of impaired bile excretion in hepatocellular cancer tissue and in the liver parenchyma surrounding metastatic liver cancers. Liver cancer navigation surgery, first developed in Japan, is also possible, and it represents one of the few fluorescence imaging techniques for cancer that have reached the stage of clinical application; with further developments in basic research, fluorescence imaging is expected to become an indispensable technique for the diagnosis and treatment of liver cancer.

Repeatability and reproducibility of manual choroidal volume measurements using enhanced depth imaging optical coherence tomography

PURPOSE

To evaluate the repeatability and reproducibility of manual choroidal volume (CV) measurements by spectral domain- optical coherence tomography (SD-OCT) using enhanced depth imaging (EDI).

METHODS

Sixty eyes of 32 patients with or without any ocular chorioretinal diseases were enrolled prospectively. Thirty-one choroidal scans were performed on each eye, centered at the fovea, using a raster protocol. Two masked observers demarcated choroidal boundaries by using built-in automated retinal segmentation software on two separate sessions. Observers were masked to each other's and their own previous readings. A standardized grid centered on the fovea was positioned automatically by OCT software, and values for average CVs and total CVs in three concentric rings were noted. The agreement between the intraobserver measurements or interobserver measurements was assessed using the concordance correlation coefficient (CCC). Bland-Altman plots were used to assess the clinically relevant magnitude of differences between inter- and intraobserver measurements.

RESULTS

The interobserver CCC for the overall average CV was very high, 0.9956 (95% confidence interval [CI], 0.991-0.9968). CCCs for all three Early Treatment Diabetic Retinopathy Study concentric rings between two graders was 0.98 to 0.99 (95% CI, 0.97-0.98). Similarly intraobserver repeatability of two graders also ranged from 0.98 to 0.99. The interobserver coefficient of reproducibility was approximately 0.42 (95% CI, 0.34-0.5 mm(3)) for the average CV.

CONCLUSIONS

CV measurement by manual segmentation using built-in automated retinal segmentation software on EDI-SD-OCT is highly reproducible and repeatable and has a very small range of variability.

[Current uses and indications for indocyanine green angiography]

A full interpretation of indocyanine green angiography images involves not only optical issues but also pharmacokinetic and biochemical aspects. These issues may involve biochemical changes in the fluorescence yield and the affinity of the molecule for lipoproteins and phospholipids. For age related macular degeneration (AMD), the advent of photodynamic therapy and especially anti-VEGF drugs has increased the use of OCT in assessing treatment response and guiding retreatment. The ease and advantages of OCT have become increasingly associated with a decreasing interest in ICG angiography, which is becoming less well suited for the current management of AMD. An aging population, the efficacy of anti-VEGF drugs and the relative rarity of polypoidal choroidal vasculopathy (PCV) in Europe are factors contributing to our proportional increase in AMD patients. However, aside from AMD, the indications for ICG angiography remain little changed over the last decade: it remains important in diagnosing PCV and choroidal hemangiomas, since their prognosis and treatment are specific. Similarly, for certain inflammatory conditions such as Multiple Evanescent White Dot Syndrome (MEWDS) or Birdshot chorioretinitis, the value of ICG angiography remains significant. In addition, for the treatment of chronic Central Serous Chorioretinopathy, ICG angiography helps to find sites of leakage which otherwise might have been missed. The ICG angiographic appearance in this setting may also have prognostic value. Although the indications for ICG angiography are currently decreasing for AMD, these other conditions represent a large enough number of patients to justify the continued use of this original test, which remains complementary to other chorioretinal imaging techniques.

Development of polypoidal lesions in age-related macular degeneration

PURPOSE

To investigate the development of polypoidal lesions using indocyanine green angiography (IA) in eyes with typical age-related macular degeneration (AMD).

METHODS

We retrospectively reviewed the medical records of 47 consecutive patients (47 eyes) with typical AMD who had been followed up with IA for at least 2 years.

RESULTS

At the initial visit, although all eyes showed classic and/or occult choroidal neovascularization (CNV) associated with AMD, no eyes showed polypoidal lesions by IA. However, during follow-up, 13 (27.7%) of the 47 eyes did show polypoidal lesions. All polypoidal lesions developed at the edge of persistent CNV or, more often, at the terminus of recently progressed CNV. Of 12 eyes with a final lesion area >8 disc area, 7 (58.3%) showed newly developed polypoidal lesions. In the eyes with these newly developed polypoidal lesions, the mean area of the vascular lesion had extended significantly from 10.50 ± 7.88 mm² to 20.87 ± 10.21 mm² during follow-up (P=0.0018).

CONCLUSION

The current observation suggests that IA of active AMD sometimes reveals polypoidal lesions if there is progression of the CNV in the subretinal pigment epithelium space.

Clinical evaluation of simultaneous confocal scanning laser ophthalmoscopy imaging combined with high-resolution, spectral-domain optical coherence tomography

PURPOSE

To evaluate the clinical relevance of a new diagnostic modality, simultaneous confocal scanning laser ophthalmoscopy (cSLO) and high-speed, high-resolution, spectral-domain optical coherence tomography (OCT), for the visualization of macular pathologies.

METHODS

OCT images and simultaneous recording of fluorescein angiography, indocyanine green (ICG) angiography, infrared, and blue reflectance ('red-free') or fundus autofluorecence (FAF) images were obtained with a novel imaging device (Spectralis HRA + OCT; Heidelberg Engineering, Heidelberg, Germany). An optically pumped solid-state laser generated the excitation wavelength (488 nm) required for blue reflectance, FAF and fluorescein angiography images. For ICG angiography and infrared imaging, diode laser sources at 790 and 815 nm were used. For OCT, 40 000 A-scans per second were acquired with 7 μm axial and 14 μm lateral optical resolution. The B-scans covering a transversal range of 30° had a scan width up to 1.536 A-scans with a digital lateral resolution of 5 μm/pixel, a scan depth of 1.8 mm with 3.5 μm/pixel digital axial resolution and a scan rate of up to 48 B-scans/second. In addition, volume scans could be obtained at 15, 20 and 30° fields of view. An integrated eye tracking allowed for live averaging of cSLO images as well as OCT B-scans.

RESULTS

Early, neovascular and atrophic age-related macular degeneration, macular telangiectasia, retinal arterial, branch vein occlusion and other pathologies were imaged, and cSLO and OCT frames correlated. Fluorescein and ICG angiographic phenomena recorded in cSLO images could be analysed accurately in corresponding OCT cross-sections. Abnormal FAF signals were correlated to alterations at the outer retinal/retinal pigment epithelial cell layer in high-resolution OCT scans. Three-dimensional OCT enabled comprehensive retinal coverage. The imaging software tracked eye movements accurately. Averaging of live B-scans enhanced image quality considerably.

CONCLUSION

  The combined cSLO/OCT system allowed for simultaneous recordings of topographic and tomographic images with accurate correlation between the confocal angiograms, FAF images as well as other imaging modes with the OCT scans. The instrument thus provides simultaneous multi-modal imaging of retinal pathologies and disease.